The subject matter disclosed herein relates to an exhaust aftertreatment system for an internal combustion engine and, more specifically, to controlling emissions from the internal combustion engine.
Engines (e.g., internal combustion engines such as reciprocating engines or gas turbines) combust a mixture of fuel and air to generate combustion gases that apply a driving force to a component of the engine (e.g., to move a piston or drive a turbine). Subsequently, the combustion gases exit the engine as an exhaust, which may be subject to exhaust treatment (e.g., aftertreatment) systems that include one or more catalytic converters (e.g., three-way catalyst (TWC) assembly, ammonia slip catalyst (ASC) assembly, etc.) to reduce the emissions of nitrogen oxides (NOX), hydrocarbons (HC), and carbon monoxide (CO). To achieve low emission levels, the catalysts operate within a relatively narrow operating window corresponding to a range of air/fuel mixtures.